usb vs bluetooth

I have 16/44.1 WAV files on an ipod nano. When playing in my car, I seemed to notice that the usb connection sounded better than bluetooth,so I went into my house where I have much better stereo and first I listened to the nano over bluetooth to a Denon AVR X-1100 W receiver feeding a pair of Polk rtia5 floorstanding speakers. Then I listened to the same song again with the nano connected to the receiver with a USB wire.The difference in SQ was STARTLING!!! The bluetooth sounded awful, the high frequencies were incoherent hash,the bass was less and muddy. The USB sounded excellent on the home system, indistinguishable (to me) ,from CD.
Has anyone else experimented with this?

It is due to the bluetooth standard and manufacturers attempting to make products backward compatible. The nice thing about bluetooth is that it is suppose to be backward compatible. I say suppose to because it is well documented to have major conflicts with other wireless based technologies like our wifi. While there has been advances in bluetooth technology, you are dependent on the type of codec that the manufacturer decides to place into there device. The norm is that even if there device supports newer bluetooth, the device will enact automatic compression's on the media being sent. In short. You have a song compressed in MP3. Your stereo will understand and decode mp3 so usb will simply send the file. Bluetooth will almost always be set to add its compression to ensure backward compatibility. This is also a similar to why you cannot send media and song data on bluetooth. Newer devises are starting to support it, but it requires both devices to reap the benefit. I simply use wired. Sounds much better and never fails.

David Harper said:

I have 16/44.1 WAV files on an ipod nano. When playing in my car, I seemed to notice that the usb connection sounded better than bluetooth,so I went into my house where I have much better stereo and first I listened to the nano over bluetooth to a Denon AVR X-1100 W receiver feeding a pair of Polk rtia5 floorstanding speakers. Then I listened to the same song again with the nano connected to the receiver with a USB wire.The difference in SQ was STARTLING!!! The bluetooth sounded awful, the high frequencies were incoherent hash,the bass was less and muddy. The USB sounded excellent on the home system, indistinguishable (to me) ,from CD.
Has anyone else experimented with this?

Click to expand...

Yeah, it is usually recommended to do a direct connection, such as USB, over a wireless connection, such as bluetooth!